SwiftUI - 更新Firebase实时数据库上的数据

Question

我已经成功地将数据显示给UI，但是我希望用户能够在点击"保存"按钮时再次更新我的数据。按钮。希望你能帮助我!

概要文件

I have successfully displayed the data to the UI, but I want the user to be able to update my data again when tapping the "Save" button . Hope you can help me!

Answer 1

有很多方法可以达到你想要的。这只是一种方法传递profileViewModel到EditProfile:

class ProfileViewModel: ObservableObject {
@Published var user = Profile(id: "", image: "", birthDay: "", role: [], gender: "", name: "")
private var ref: DatabaseReference = Database.database().reference()
func fetchData(userId: String? = nil) {
// 8hOqqnFlfGZTj1u5tCkTdxAED2I3
ref.child("users").child(userId ?? "default").observe(.value) { [weak self] (snapshot) in
guard let self = self,
let value = snapshot.value else { return }
do {
print("user: (value)")
self.user = try FirebaseDecoder().decode(Profile.self, from: value)
} catch let error {
print(error)
}
}
}

func saveUser() {
// save the user using your ref DatabaseReference
// using setValue, or updateChildValues 
// see https://firebase.google.com/docs/database/ios/read-and-write
}
}
struct EditProfile: View {
@ObservedObject var profileViewModel: ProfileViewModel  // <--- here
var body: some View {
VStack {
Text(profileViewModel.user.name)  // <--- you probably meant TextField
.font(.custom("Poppins-Regular", size: 15))
.foregroundColor(Color.black)
Text("(profileViewModel.user.birthDay)!")
.font(.custom("Poppins-Regular", size: 22))
.fontWeight(.bold)
.foregroundColor(Color.black)
Text("(profileViewModel.user.gender)")
.font(.custom("Poppins-Regular", size: 22))
.fontWeight(.bold)
.foregroundColor(Color.black)
Text(profileViewModel.user.role.first ?? "")
.font(.custom("Poppins-Regular", size: 22))
.fontWeight(.bold)
.foregroundColor(Color.black)

Button(action: {
// save the profileViewModel.user to database
profileViewModel.saveUser()  // <--- here
}) {
Text("Save")
}
}
.padding()
}
}
struct CategoriesView: View {
@ObservedObject var viewModel = SectionViewModel()
@EnvironmentObject var loginViewModel : LoginViewModel
@StateObject var profileViewModel = ProfileViewModel()

var body: some View {
ZStack {
VStack (alignment: .leading, spacing:0) {
EditProfile(profileViewModel: profileViewModel)  // <--- here
.padding()
.padding(.bottom,-10)
}
}
.onAppear() {
self.viewModel.fetchData()
profileViewModel.fetchData(userId: loginViewModel.session?.uid)
}
}
}

EDIT1:关于更新后的代码。

在你的新代码，在ProfileHost你没有传递ProfileViewModel。用途:

NavigationLink(destination: ProfileEditor(profileViewModel: viewModel)) {
ProfileRow(profileSetting: profile)
}

和在ProfileEditor取代profile与profileViewModel.user
你可能需要调整profileItem，并把它放在.onAppear {...}。像这样:

struct ProfileEditor: View {
@Environment(.presentationMode) var presentationMode: Binding<PresentationMode>
@ObservedObject var profileViewModel: ProfileViewModel
@EnvironmentObject var loginViewModel: LoginViewModel

let profileLabel: [String] = ["Name", "Account", "Gender", "Role", "Email"]
@State var profileItem: [String] = []
@State var profileEditorRow: [ProfileEditorItem] = []

var body: some View {
VStack {
ForEach(profileEditorRow) { editor in
if editor.id == 5 {
ProfileEditorRow(editor: editor, showLastLine: true)
} else {
ProfileEditorRow(editor: editor, showLastLine: false)
}
}
Button("Save") {
profileViewModel.updateData(userId: loginViewModel.session?.uid)
}
}
.onAppear {
profileItem = [profileViewModel.user.name,
profileViewModel.user.birthDay,
profileViewModel.user.gender,
profileViewModel.user.role.first ?? "",
profileViewModel.user.birthDay]
for n in 1...5 {
profileEditorRow.append(ProfileEditorItem(id: n, label: profileLabel[n-1], item: profileItem[n-1]))
} 
}
}

}

update function

func updateData() {
ref.("users").child(user.id).updateChildValues([
"name": user.name,
"birthDay": user.birthDay,
"gender": user.gender,
"role": user.role.first ?? ""])
}

并在ProfileEditor中使用:

Button("Save") {
profileViewModel.updateData()
}